It is well known that the Long Term Evolution (referred to as ‘LTE’ hereinafter), so named because it evolutionized the 3rd generation (referred to as ‘3G’ hereinafter) mobile communication in long term perspective, is one of the strong candidates for the 4th generation mobile communication technology in parallel with the Wibro Evolution.
This LTE is based on the ‘Release 8’ that is finalized as a standard specification in December 2008 by the 3rd Generation Partnership Project (referred to as ‘3GPP’ hereinafter) which standardizes 3rd mobile wireless communication; the channel bandwidth is from 1.25 MHz to 20 MHz, and the maximum transmission speed of the downlink is 100 Mbps based on 20 MHz bandwidth, and the maximum transmission speed of the uplink is 50 MHz.
Wireless multiple access and multiplexing method is based on orthogonal frequency-division multiplexing (referred to as ‘OFDM’ hereinafter), and high speed packet data transmission method is based on multiple-input and multiple-out (MIMO). LTE Advanced is an evolutionized version of the above-described LTE, it will be referred to as ‘3GPP LTE’ hereinafter.
Meanwhile, There are two types of method supporting uplink (referred to as ‘UL’ hereinafter) and downlink (referred to as ‘DL’ hereinafter) allocation for an LTE system. The first method is a frequency division duplexing (referred to as ‘FDD’ hereinafter) which separates UL and DL by frequency band; the second method is time division duplexing (referred to as ‘TDD’ hereinafter) which separates UL and DL by time domain.
FIG. 1 is a table defining UL and DL transmission periods for the frame structure of an LTE system adopting TDD method (referred to as ‘LTE-TDD’ hereinafter). UL and DL transmission periods for an LTE-TDD method in the time domain are determined by the UL/DL configuration signal whose number classifies UL and DL into a total of seven types as shown in FIG. 1. In FIG. 1, ‘D’ stands for a DL sub-frame, ‘U’ stands for a UL sub-frame, and ‘S’ stands for a special subframe inserted when switching from a DL subframe to an UL subframe; one frame is comprised of 10 ms and each frame is comprised of 1 ms, hence there is a total of 10 subframes per one frame. For example, for a configuration 1 in FIG. 1, switching from DL to UL is occurring for every 5 ms; hence, there are four DL subframes, four UL subframes, and two special subframes per one frame.
The UL/DL configuration number must be obtained in advance in order to analyze UL/DL signal of an LTE-TDD signal according to the above-described structure. According to the Technical Specification (3GPP TS 36.211 V9.0 (2008-12)), the UL/DL configuration numbers are transmitted via Broadcast Control Channel (referred to as ‘BCCH’ hereinafter) of the DL, therefore the BCCH must be decoded in order to obtain configuration number at a base station or terminal.
Signal analyzers for analyzing the LTE signals have been developed without BCCH decoder considering complexity thereof; therefore there has been inconveniences that users must imput UL/DL configuration numbers into the signal analyzer in order to analyze LTE-TDD signals.